Points load tester should consider

From last 6-7 months, I was working closely on load testing of a couple of application. While working on it I realized few capabilities a responsible person should have.

1) One should have a good understanding of the application domain, even more than a functional tester. If one needs to craft the load test plan then he should be aware of how the user does use it. He should clarify his assumptions of how the system will be used. Recommended way is to observe few users, to understand better about application usage.

2) one should have a better understanding of the application architecture, how components interact? What is the difference between non-prod and prod system from an infrastructure perspective? What will be the network bandwidth? What will be the average think time? etc.

3) One should be technically strong and creative enough to gather the load test data or way to generate the load test data. This one is very critical to building independent, low maintenance, automated load test. One can have a utility which will run prior to the Load test to generate test data. A process of test data management is the key to having successful continues delivery with zero human interaction.

4) One should be able to identify the peak load details based on historical data. If the historical data is not available then one needs to come up with the approximate numbers. As load test may run for 1-2 hour, one needs to have a good combination of different transactions. NOTE: once you baseline the performance of each transaction through the full test (1-2 hours), in CD you can have tested for lesser numbers just to verify if the build is not impacting the baseline numbers. For major builds, one can run the full test.

5) And the key and important one, expert knowledge of the load testing tool, protocols, command-line or configuration options, how the tool works etc.

Points load tester should consider

Protobuf Performance Comparison and points to make decision

What is Porotbuf?

Developed by Google for object serialization, its open source library and available for multiple languages. It’s a Fast buffer which does the object serialization, you can consider same as XML but it’s more faster, takes less size, serialization and deserialization is faster than any other available approach.

What is the procedure?

One need to define the object structure, it can be done by defining the .proto file, which defines required, optional fields of the object.

Once proto file is generated, one need to use supplied code generator, this utility is language specific and generates language specific code. If it’s used for java then you can consider that this utility generates the java pojo for serialization and de-serialization.

Now using supplied library, generated beans/models and .proto files, one can serialize or de- serialize the response.

Why should I use it?

  • JSON and XML transmit data with metadata details, and which adds load on payload, requires more memory compared to Protobuf. Protobuf compress the data, generate dense data. If compared to XML Fast buffers takes almost 1/3rd size and if compared to JSON then its ½.
  • JSON and XML are more readable and not secure to transmit data over the network. If you want your response shouldn’t be readable by user then you can use Protobuf.
  • Consumer of the service needs the .proto file to de-serialize the object stream.
  • Less CPU and Memory will be consumed for serialization and de- serialization, so processing time on mobile devices is faster compared to JSON


Here I considered the web application which sends data using REST service, and a web page which renders the data on screen. I have used total time to render a page using JSON and Proto, end-to-end to make sure I am covering, serialization, data transmission, de- serialization and DOM rendering. I compared it with different network speed, broadband, 3G and 2G.


Network JSON Proto
Time Broadband 555 MS 359 MS
Payload size Broadband 1.2 MB 684KB
Time 3G (1Mb/S) 7.93 S 4.6 S
Payload size 3G (1Mb/S) 1.2 MB 684KB
Time (ms) 2G 22 S 13.73 S
Payload size 2G 1.2 MB 684KB
Network JSON Proto
Time Broadband 288 MS 293 MS
Payload size Broadband 512 KB 292 KB
Time 3G (1Mb/S) 2.91 S 1.86 S
Payload size 3G (1Mb/S) 512 KB 292 KB
Time 2G 9.80 S 6.06 S
Payload size 2G 512 KB 292 KB
Network JSON Proto
Time Broadband 229 MS 233 MS
Payload size Broadband 302 KB 269 B
Time 3G (1Mb/S) 318 MS 331 MS
Payload size 3G (1Mb/S) 302 KB 269 B
Time 2G 723 MS 808 MS
Payload size 2G 302 KB 269 B

Points to consider

  • If payload is larger than 300KB then one can gain more from speed and performance perspective.
  • If application needs to send smaller chunks of data (IoT case) then, need to think about if system really needs the status real time or if we can merge the events triggered and upload the payload after an interval. Need to ask question, which one is more applicable? sending 40KB payloads 10 times or sending a 400KB once?
  • Does application need object serialization which is platform independent, not human readable and takes lesser memory? If yes the go for ProtoBuf
  • I haven’t tested the serialization and de-serialization performance on smaller devices like mobile and IoT one. Definitely those will one more aspect to consider.
  • It’s not limited only for REST services which returns the data in JSON or XML to compare with, one can use Protobuf for MQ, RFC.
  • Protobuf makes more sense if you have same web application or rest services to be used by desktop and mobile devices.

I used Spring Boot for REST service, bytebuffer.js on JS side and Google Protocol buffer libraries.

Protobuf Performance Comparison and points to make decision

Raspberry Pi 2 – Sonic Pi

Ordered Raspberry Pi 2 as soon as I came to know its available for sale 🙂

First impression, it’s really fast (if you have used previous version you will agree). I tried both linus distributions, Raspbian and Snappy Ubuntu, didn’t got much time to explore the Ubuntu one, but my kid liked the Raspbian most, because of the Sonic Pi and Mathematica.

Sonic Pi is the awesome open source programming tool for kids, and its fun while you learn programming. It covers, loops, conditionals, concurrency and data structures.

Raspberry in action :


Snappy Ubuntu on Sony :


Few updates in Raspberry Pi 2, which I loved

New 900MHz quad-core processor, 1GB memory and Combined 3.5mm audio jack and composite video.

Using Male 3.5mm to 3 RCA AV Audio Video Male Converter Cable, you can connect your Raspberry to any TFT screens or to TV which support RCA Video, cheaper one are the used in car for rear view.


Or you can opt for a TFT LCD screen


Raspberry Pi 2 – Sonic Pi